| dc.description.abstract | The impact of climate change on the environment cannot be ignored. In recent years, the frequency of droughts, heatwaves, and heavy rains has surged worldwide. Reducing greenhouse gas emissions can mitigate the global warming and decrease the occurrence of extreme weather, highlighting the urgency of carbon reduction. Hydrogen is a clean fuel with potential as a zero-carbon energy carrier. Decomposing ammonia to produce hydrogen and integrating it into coal on gas power systems to partially replace coal and natural gas can improve power generation efficiency, making it a key strategy for countries to achieve net-zero carbon emissions. This study involves the preparation of 10 wt% Fe-Ni/MgO and Ru/MgO catalysts via impregnation method. It focuses on two main parts: application of the thermal system and the plasma-catalyst system for ammonia decomposition to produce clean hydrogen. The study explores the effects of operating parameters (space velocity, concentration, and operating voltage) on ammonia decomposition efficiency. The experimental results show that the ammonia decomposition rate achieved with plasma + Ru/MgO catalyst system first decreases and then increases with space velocity, a trend different from that of the pure plasma system and the plasma + Fe-Ni/MgO catalyst. At a space velocity of 1800 mL/g·h, the plasma + Ru/MgO catalyst system achieves the highest ammonia decomposition rate (75.2%). The hydrogen energy efficiency increases with increasing voltage, showing a unique upward trend among the systems. At high operating voltages (≥12 kV) and a space velocity of 7200 mL/g·h, the conversion of NH3 achieved with plasma-catalyst system surpasses that of the pure plasma system, demonstrating the synergistic effect of the plasma-catalyst combination. At high operating voltages, the system with the added catalyst exhibits better hydrogen energy efficiency. In terms of space velocity, at low operating voltages, the hydrogen energy efficiency achieved with pure plasma system is superior to that of the plasma-catalyst system with longer gas residence time (lower space velocity). At a space velocity of 7200 mL/g·h, the hydrogen energy efficiency of the plasma-catalyst system exceeds that of the pure plasma system. Regarding ammonia feed concentration, at high operating voltages, the plasma-catalyst system shows a trend with the hydrogen energy efficiency at a 20% feed concentration > 30% > 10%. This study has demonstrated that combined plasma catalysis is effective in decomposing ammonia to generate hydrogen and has the potential for industrial application. | en_US |